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Area forecast discussion 
National Weather Service New Orleans la
1203 PM CDT Wednesday Jul 23 2014

Aviation...
VFR conditions are expected to prevail outside any localized
convective impacts. Much of the convection should abate by 01z and
redevelop generally after 16z Thursday. 24/rr

&&

Previous discussion... /issued 422 am CDT Wednesday Jul 23 2014/

Synopsis...
latest upper air analysis showed a cyclonic circulation over
southeast Louisiana and a large anticyclonic circulation over
Colorado. 500 mb temperatures are -8c across the east half of the forecast
area...a relative cool pocket around and east of the upper level low.
GFS and Euro initialized a vorticity maximum over southeast Louisiana and
southern Mississippi. Latest surface analysis revealed a very weak
pressure gradient from south Texas to South Carolina with a 2mb
difference. Precipitable water values on a planer view at 12z
showed the wrap around moisture west edge has made it to Lafayette
with 1.9 inches at Slidell and 1.5 inches at Lake Charles. 18

Discussion...
with a relaxed pressure gradient...a cool 500 mb temperature aloft and
elevated precipitable water values in place...convection should develop around sea
breeze boundaries and in land. The upper level low will shift west
through today and the dry air entrainment to the low and middle layer
northerly flow are expected to shift west. Therefore...expected
scattered storms across the area today and a few strong across
east central Louisiana west of I-55 and southwest Mississippi.
Gusty winds from strong thunderstorms will be the main threat
today. The upper level low will continue to shift west to
southwest tonight and Thursday. The ridge axis from the upper
level high out west will provide some drying in the middle layers
across the forecast. Low level moisture will remain elevated but
precipitable water values will slowly decrease from 1.8 inches Thursday to 1.5 to
1.6 inches Friday and Saturday. In addition...500 mb temperatures will rise
to -6c by then. Some suppressive factors will curtail convection a
bit Friday through Sunday. However...intense surface heating and
low level moisture can still yield isolated convection late in the
day. A few areas may reach the middle 90s for highs Friday through Sunday.

Next week models still point to an active jet pattern and an upper
trough that will dig across the the eastern part of the country
Sunday into Monday. This will result in a cold front being pushed
into the lower Mississippi Valley and north half of forecast area
Tuesday through Wednesday. Rain chances will increase along and
south of the front Monday and Tuesday. 18

Aviation...for the most part VFR conditions can eb expected. There
may be a isolated areas of tempo MVFR visibilities until sunrise but after
that VFR conditions should rule the day outside of convection.
Convective coverage should be greater today than yesterday so look
for most terminals to be impacted by convection around midday and
through the afternoon. /Cab/

Marine...the marine zones will remain fairly quiet through much of
the forecast. Most of the time winds will remain at or below 10 kts but
brief periods of 10-12 kts during the overnight hours east of the MS
Delta will occur. Seas will generally remain 3 feet or lower. Models
continue to indicate another rare cold front approaching the coast
next week. /Cab/

Decision support...
dss code...green.
Deployed...none.
Activation...none.
Activities...slurry support

Decision support services (dss) code legend
green = no weather impacts that require action
blue = long fused watch/warning/advisory in effect or high
visibility event
yellow = heightened impacts with short fused
watch/warning/advisory issuances; radar support
Orange = high impacts - slight to moderate risk severe; nearby
tropical events; hazmat or other large episodes
red = full engagement for moderate to high risk severe
and/or direct tropical threats; events of National
significance

&&

Preliminary point temps/pops...
mcb 91 70 93 70 / 40 20 30 20
btr 92 72 94 73 / 50 20 30 20
asd 90 71 92 72 / 30 20 30 20
msy 90 75 91 77 / 30 30 30 20
gpt 89 75 91 74 / 30 20 30 20
pql 89 71 91 72 / 30 20 30 20

&&

Lix watches/warnings/advisories...
la...none.
GM...none.
MS...none.
GM...none.
&&

$$

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